Speed-changing device.



No. 816,369. PATENTED MAR. 27, 1906. 0. I'. PERSSON. SPEED CHANGING DEVICE. APPLICATION FILED JULY 2o, 1904j 3 SHEETS-SHEET 1.

Invent@ ,f E Persson,

Ott o BJ 'mmlml No.8l6,369. PATENTED MAR. 27, 1906. O. E. PERSSON.

SPEED CHANGING DEVICE.

APPLICATION FILED JULY20.1904.

3 SHEETS-SHEET 2 Wtmess es: 2 ITM/entom n .I B Otto FPesson, m2 ZM y PATENTED MAR. 27, 1906.

0. E. PERSSDN. SPEED CHANGING DEVICE.

APPLICATION FILED JULY 2o, 1904.

3 SHEETS-SHEET 3.

I Ivm/enter; Ottooerssofw,

IIIIIIIIIIIHIIIIINII Witnesses:

tional elevation of the same.

UNITEDv STATES PATENT OFFICE.

OTTO F. ,PERSSON` OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, AUORPORA'IION OF NEW YORK.

SPEED-CHANGING DEVICE.

Specification of Letters Patent.

Patented Mach 27. 190e'.

Application filed July 20, 1904i Serial No. 217,311.

To/nl whom, it riz/ay concern.'

Be it known that I, OTTO F. PnRssoN, a citizen of the United States, residing at Lynn, in the county of Essex and State of Massachusetts, have invented certain new and useful Improvements in Speed-Changing Dev ices, Aof which the following is a specification.

This invention relates to mechanism for varying the speed of a driven shaft without altering the speed 'of the driving-shaft.

It has for it-s object to provide a mechanism of improved construction which will effectively transmit power at varying speed with' minimum loss in transmission.

The nature and scope of my invention will be set forth more fully in thedescription and in the claims appended thereto.

In the accompanying drawings, Figure 1 is an' elevation ofan electric motor equi ped with my invention. Fig. 2 is a longitu inal sectional elevation of the speed-changing device on a larger scale. Fig. 3 is a cross-sec- Fig. 4 is atop lplan view wit-h the upper half of the casing removed. Fig. 5 is a side elevation on the line 5 5, F ig; 6, of the pinion-shifting levers, partly broken away. Fig. 6 is a vertical cross-section ofthe same on the line 6 6, Fig. 5. Fig. 7 is a horizontal sectionon the line 7 7, Fig. 6, and Fig. 8`showsthe mode of fastening t-he pulley to the shaft.

The driving-shaft 1 may be actuated in any suitable manner-as, for instance, by an electric motor 2. The shaft passes longitu# dinally through a casing 3, divided into upper and lower halves on the horizontal plane ofthe shaft. The lower half has bearings 4 for the shaft. keyed or otherwise Arigidly secured to one half of the -shaft inside the casing. A similar gear 6 is firmly secured to a'sleeve 7, which is rotatable on the other half of the shaft inside the casing. The sleeve extends outside of the casing and carries a belt-pulley 8 or other means of transmitting its motion to any desired mechanism.

y The two friction-gears are conico-heini- ,spherical with their bases adjacent, but not 1n `contact. More accurately speaking, .they

form together a spindle whose surface is eneratedby a segment of a circle revolver on its chord, the radius of the circle being pref- A friction driving-Gear 5 isy bled side by side on a bushing l() and firmly fastened together, as by rivets 11.

The disks are preferably compressed between a collar 12 at one end of the bushing and a flanged nut 13l screwed on the other end thereof. The adjacent ends of the gears are preferably faced with a 'sheet 'ofmetal 14.

` One or more pairs of friction-pinions 15 16 15. 16 are engaged, respectively, with the gears 5 6 and are connected together in order to transmit motion from the gear. 5 to the gear 6y and its pulley 8. The pinions are preferably secured on short shafts 17, Which are journaled in fixed bearings 18, arranged at an angle with each other. The shafts are connected in any suitable manneras, for instance, by bevel-gears 19. AThe pinions in each pair are'spaced apart about the length of one of the gears 5 or 6, so that they can be shifted along said vgears to vary their points of contact therewith, one approaching the larger end of its gear as the other approaches the smaller end of the other gear, and vice versa. Bylthis means the relative speeds of the two gears will be varied, though the absolute speed of the driving-gear 5 remains constant.

If only one pair of pinions is used, it is simply necessary-to mount them on a lever fulcrumed on an axis concentric With the curve of the'conoidal gears but I' prefer to use two airs of pinions, one above and the other be ow -`-the gears, and'in order to move both pairs simultaneously in the same direction they must be supported and `connected in a certain manner, as will now be described.

On the inside of the lower half of the casing are lugs 20, to which are firmly bolted the bridges 21 and the han ers 22. The bearings 18for t-he upper pair o pinions 1.5 16 are fastened to a lever 23, preferablya bifurcated lever, Whose legs are fulcrumed to the hangers. The lower pair of pinions 15l 16 is supported by a lever 24, preferably a U-shaped lever, whose arms are fulcrumed to the bridges. In each case the axis of the fulcrum'is concentric With the curve of the wears. 'In order to` press the pinions constantly a' ainst thesurface of the gears, the legs of t e upperlever IOO w eiasee and the arms of the lower lever are made in 4two parts-overlapping each other. On one part 2'5" are lugs 26, which face lugs 27 on the other part 28, and betxi'e'eriv each pair of lugs is a helical spring 29 under compression. These springs constantly pull the upper pinions downward and lift the lower pinions upward against the surfaces ofthe gears 5 6. To keep the parts 25 28 inv .alinement, they are preferably provided withy longitudinal registering slots 30, in which fits a block 31 31, the two blocks on each side being pivotally supported at their middle points on a pin 32, projecting inwardly from a slide 33, fit? ting between horizontal guide-bars 34, se-. cured to the lugs 20. A hand-lever 35 is secured to the upper lever 23 and projects through a slot inthe upper half of the casing. it is provided with a latch 36, cooperating with a notched quadrant 37 on the top of the casing, so that the pinions canbe adjusted .to any desired position.

The operation of the device is as follows: Vith the parts standing as shown in Fig. 2 the pinions bear on equal diameters of the gears, so that the speed of the pulley 8 is the saine as that ,of the driving or motor shaft. By moving the lever 35 to the right (in Figs. 1 andl 2) the upper lever 23 turns on its fulcrunis in the haiwers 22 and. carries the blocks 31 31 and the slides 3i to the right. As the blocks 3l engage with tue arms of the lower lever 2-1 the latter is also moved to the right, turning on its fulcrunis in the bridges 21. The result of this action is to shift. both pairs of pinions to the right in Fig. 1, so that the pinions 15 15 will engage with a larger diameter of the gear 5, while the pinions 16 16 will move out to a smaller diameter of the gear 6. This will cause the pulley 8 to run faster than the motor-shaft- A'niovement of the lever 35 to the left from its position in Figs. 1 and 2 will causethe pulley S to run slower than the motor-shaft- The change can be made while the motor is ruiming, and thus the speed of the pulley can be varied within wide limits without altering the speed of the motor. The device is therefore especially useful in connection with inductionmotors, which give the best efficiency at a given constant speed.

\Yhat l claim as new, and desire to secure b v Letters Patent of the United States, is-

l. ln a speed-clianging device, the combination with two conoidal friction-gears independentlv rotatable on a coninion axis with their bases adjacent, of a paii of connected pinions engaging respectively with said gears, and nie'ans for moving said pair ot pinions .vigiiig respectively Willi gli titille' t* said gears, and means for simultaneously moving both pairs of pinions lengthwise of said gears and in the same direction.

3. In a speed-changing device, the combination with a shaft, of a conoidal frictiongear secured fiiereto, a sleeve rotatable on said shaft, a conoidal friction-gear secured on said sleeve with its base adjacent to that of the other gear, one or more pairs of connected pinions engaging with said gears, and means for moving them lengthwise thereof. Y'

4. In a speed-changing device, the combination with two conoidal friction-gears independently rotatable on a common axis with their bases adjacent, of a lever fulcruined at a point concentric wit-h the curve of said gears, and a pair of connected pinions mounted on said lever and engaging with said gears.

5. In a speed-changimT device, the combination with two conoidal:` friction-gears independently rotatable on a common axis with their bases adjacent, of a lever fulci'uined at a point concentric with the curve of said gears, two short shafts mounted on said lever at an angle with each other, pinions mounted on the shafts which engage respectively with said gears, and means connecting said shafts.

6. In a speed-changing device, the combination with two conoidal friction-gears independently rotatable on a common axis with their bases adjacent, of a lever fulcruined at a point concentric with the curve of said gears, two short shafts mounted on said lever at an angle with eachother, a. pinion on each shaftengaging with a gear, and bevel-gears connecting the adjacent ends of said shafts.

7. 1n a speed-changing device, the combination with two conoidal friction-gears independently rotatable on a common axis with their bases adjacent, of two levers fulcruined on opposite' sides of said axis at points concentric with the curve of the gears, pairs of pinions carried by said levers and engaging "with said gears, and connections between said levers whereby both move simultaneously in the saine direction lengthwise of said gears.

8. In a speed-changing device, the combination with two coiioidal friction-gears independently rotatable on a common axis with their bases adjacent, of two levers pivoted on opposite sides of said axis at points coneentric with thee-urve of the gears. pairs of pitiions carried by said levers and engaging wit li said gears, a. slide iiiovalile in a line transverse to the line joining the two pivots, and blot-lts; pivotcd to said slide and engaging with said levers.

Si. ln a speed-tlianging device. the coinliiiaitioiiwitli two eonoidal friction-gears indepeiideiitlwv rotatable on a eoiiinioii axis wit'li their bases adjacent, olI two levers: pivoted on opposite sides of said axis and provided with long itiidii'ial slots, guide-bars extending perpei`a`lifi il.:ir to the lino joining the pivots. a

ICO

slide movable between said bars, blocks fittin in the lslots in the levers and pivoted to sai slide, and pairs of pinions carried by said levers and engaving with said'gears.

10. In a Spee -changing device, the combination with a easing, of a shaft journaled therein, two conoidal rictionears, one fast and the other loose on said sha t, a bridge and gage the pper side ofthe gears, and connections between said levers.

11. In a speed-changing device, the combination of two overlapping members, each provided with lateral lugs, Compression-springs seated between saidlugs, and means for keepin the two members in line., p zo n witness whereof I have hereunto' setlmy hand this 1st day of July, 1904:.`

v OTTO I". PERSSON. Witnesses:

DUGALD WOK. MCKILLOP, v JOHN A. McMANUs. 

